I am thinking of fitting some new wheels(mavic crosstrail) and going ust ,will I notice a difference ?

Yes.

Most definately – wheels are the best place to save a bit of weight. Just make sure they are still robust enough for your riding.

if it’s genuinely saving you that much weight then yes, you will certainly notice the difference. It wont necessarily make you that much quicker, but the bike will feel a lot more responsive underneath you. remember that weight is as far away from your centre of gravity as you can get on the rider/bike combination and requires the most effort to move around, hence is a great place to save weight.

It will make you slightly quicker from the reduction in rotational inertia which is slowing down all the little accelerations a wheel does on every pedal stroke.

That’s nearly 800g.. If the new wheelset is 1500g (which is quite light), then your old wheelset must be 2300g? Which is proper heavy.

It will make you slightly quicker from the reduction in rotational inertia which is slowing down all the little accelerations a wheel does on every pedal stroke.

Really?

The theory may well be correct, but if wheels accelerated during each pedal stroke, they’d get to the top of the hill 5 minutes before you did. When you accelerate, you accelerate everything, you, bike, tyres, jelly beans in your pocket, hair, teeth and so on.

Hell yeah. It’ll be pretty obvious as soon as you ride them.

Yes. Not only will it be easier to pedal, it will jump (if the wheels are strong enough) and change direction better as well.

Weight saving calculations = hope pro2 on mavic en521 rims 2100 g 2 x inner tubes @ 140 g each =280 total 2380 g
mavic crosstrail 1685 g a saving of 695 g or 1.5 lb (not 1.7 lb as first stated)

You will still notice it, 1lb off the wheels is pretty noticeable. Overall it’s the best place to lose weight on the bike.

If you want to get it nearer to 1.7 and have the money to bling it out perhaps you could build it with some light areospokes like Sapim CX Rays?

I don’t see how you’ve got that build below 1700 grams though, Stans Flows are heavier than that (by a fraction) when laced to Sapim CX Rays and they are a lighter rim.

Remember to factor in the weight of the sealant- OK you don’t need sealant with UST, but it’s still a very good idea. And UST tyres tend to be heavier (though not always)

There’s a risk this thread’ll degenerate into a pointless argument about weight saving… But IMO and IME, there’s no chance at all that you won’t notice a difference.

They’ll probably feel a bit more sprightly, yes.

Massively!!

Lighter wheels feel faster and more lively, but often the payback is they’re not as strong.

Don’t go so light that they compromise your riding, but I’d say it’s generally accepted that running as light wheels as you can get away with reasonably is not a bad idea.

You’re not going to lose as much weight as you think though. Mavic Crosstrails at roughly 1700g aren’t especially light considering. They’re 400g lighter than your current wheels granted, but when you add the valves, sealant and heavier tyres you’ll need to reliably run tubeless, the weight you lose in the inner tubes is negated, and so is some of the 400g weight saving on the wheels.

I’d warrant you’ll lose 250-300g of overall rotating weight, which is not insignificant in itself, but probably not as much as you were hoping for.

In that case get some Flows they are brilliant.

I know lot of people hate Superstar but I had a set of crest wheels from then and they’ve been great. These are superb value for money!

http://superstar.tibolts.co.uk/product_info.php?cPath=40&products_id=498

I’ve just knocked 1.33lb off my wheels weighed with brake discs, UST tyres and sealant on my 29ER and it feels much lighter and really glad I did it.
I went round my local trail at Dalby Forest and knocked 17 minutes off my previous time as I was faster on the climbs.
I got some Easton Havens from CRC 50% off which are UST and some Maxxis Ardent LUST tyres and decided to chuck in some Stans sealant for added peace of mind.

If your getting into weighing tubes, weigh your tyres too. There is a massive difference in those, some are crazy heavy. If your going tubless try to run standard kevlar bead tyres the propper UST tyres are pretty heavy.

If you lay in a dark room every day sobbing as you **** into a sock then you may not notice. if you ride your bike, you will